linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: "Michael Kelley \(EOSG\)" <Michael.H.Kelley@microsoft.com>
Cc: "mhkelley58\@gmail.com" <mhkelley58@gmail.com>,
	"gregkh\@linuxfoundation.org" <gregkh@linuxfoundation.org>,
	"linux-kernel\@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"devel\@linuxdriverproject.org" <devel@linuxdriverproject.org>,
	"olaf\@aepfle.de" <olaf@aepfle.de>,
	"apw\@canonical.com" <apw@canonical.com>,
	"jasowang\@redhat.com" <jasowang@redhat.com>,
	"marcelo.cerri\@canonical.com" <marcelo.cerri@canonical.com>,
	Stephen Hemminger <sthemmin@microsoft.com>,
	KY Srinivasan <kys@microsoft.com>
Subject: Re: [PATCH char-misc 1/1] Drivers: hv: vmbus: Make synic_initialized flag per-cpu
Date: Tue, 28 Aug 2018 22:59:47 +0200	[thread overview]
Message-ID: <87va7uxl4s.fsf@vitty.brq.redhat.com> (raw)
In-Reply-To: <CY4PR21MB077375C31D9211486C328328DC0A0@CY4PR21MB0773.namprd21.prod.outlook.com> (Michael Kelley's message of "Tue, 28 Aug 2018 20:20:19 +0000")

"Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com> writes:

> From: Vitaly Kuznetsov <vkuznets@redhat.com>  Sent: Wednesday, August 1, 2018 2:26 AM
>
>> > I was trying to decide if there are any arguments in favor of one
>> > approach vs. the other:  a per-cpu flag in memory or checking
>> > the synic_control "enable" bit.   Seems like a wash to me, in which
>> > case I have a slight preference for the per-cpu flag in memory vs.
>> > creating another function to return sctrl.enable.  But I'm completely
>> > open to reasons why checking sctrl.enable is better.
>> 
>> Just a few thoughts: reading MSR is definitely slower but we avoid
>> 'shadowing' the state, the reading is always correct. In case there's a
>> chance the SynIC will get disabled from host side we can only find this
>> out by doing MSR read. This is a purely theoretical possibility, I
>> believe, we can go ahead with this patch.
>
> Vitaly -- just to confirm:  you are OK with the patch as is?  (I'll
> check, but I may need to rebase on the latest code.)

Yes, feel free to use my R-b tag.

-- 
  Vitaly

      reply	other threads:[~2018-08-28 20:59 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-31  2:34 [PATCH char-misc 1/1] Drivers: hv: vmbus: Make synic_initialized flag per-cpu mhkelley58
2018-07-31 11:19 ` Vitaly Kuznetsov
2018-08-01  5:47   ` Michael Kelley (EOSG)
2018-08-01  9:26     ` Vitaly Kuznetsov
2018-08-28 20:20       ` Michael Kelley (EOSG)
2018-08-28 20:59         ` Vitaly Kuznetsov [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87va7uxl4s.fsf@vitty.brq.redhat.com \
    --to=vkuznets@redhat.com \
    --cc=Michael.H.Kelley@microsoft.com \
    --cc=apw@canonical.com \
    --cc=devel@linuxdriverproject.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=jasowang@redhat.com \
    --cc=kys@microsoft.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marcelo.cerri@canonical.com \
    --cc=mhkelley58@gmail.com \
    --cc=olaf@aepfle.de \
    --cc=sthemmin@microsoft.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).